1.2   Text Questions :

Answer the questions :

(1)  What is an ecosystem.
Ans: The system formed by the interaction of all living organisms with each other  and with the physical and chemical factors of the environment in which they live, all linked by the transfer of energy and material is called an ecosystem.

(2) What do you mean by natural environment.
Ans: The basic components and organisms that are naturally present in the environment, without any human involvement  like land, water, air, plants and animals comprise the natural environment .

(3) What are the major components of the environment.
Ans: The major components of the environment are :
i) Natural components like air, water, land, living things.
ii) Human made components .
iii) Human components ( living beings) .

(4) Give four examples of human made environment.
Ans: Four examples of human made environment are buildings, parks, industries and bridges.

(5) What is lithosphere.
Ans: The solid crust or the hard  top layer of the earth is called the lithosphere. It is made up of rocks and minerals and covered by a thin layer of soil. It is an irregular surface with various landforms like mountains, plateaus, plains  etc.

(6) Which are the two major components of biotic environment.
Ans: Plants and animals are the two major components of biotic environment.

(7) What is biosphere.
Ans:  Biosphere or the living world is the narrow zone of earth where land, water and air interact  with each other to support life. The plant and animal kingdom together form the biosphere.

Tick the correct answer:

(i)  Which is not a natural ecosystem.
(a) Desert                (b) Aquarium √            (c) Forest

(ii) Which is not a component of human environment.
(a) Land √             (b)  Religion                   (c) Community.

(iii)  Which is a human made environment.
(a) Mountain        (b) Sea                             (c) Road √

(iv) Which is a threat to environment.
(a) Growing plant             (b) Growing population √        (c) growing crops.

Match the following:

1.  Biosphere          (a) blanket of air which surrounds the earth.
2.  Atmosphere      (b) domain of water.
3.  Hydrosphere    (c)our surroundings
4.  Environment    (d) narrow zone where land, water and air  Interact .

Answers :

1.  Biosphere            (d) narrow zone where land, water and air interact.
2.  Atmosphere       (a) blanket of air which surrounds the earth.
3.  Hydrosphere     (b) domain of water.
4.  Environment     (c) our surroundings.

Give reasons :

 1.  Man modifies his environment.
Ans : Man modifies his environment to fulfill his basic needs, as it is the basic life support system. He builds houses to live in and industries to  work in , which modifies the environment and also his mineral wealth.

2.  Plants and animals depend on each other.
Ans: Plants and animals depend on each other for their own good. Plants release oxygen that animals breathe and absorb carbon dioxide that animals release.